When Yvon Rioux, a teacher and singer, witnesses the brutal death of a former student, gunned down before his eyes, his world collapses. Traumatized, he develops post-traumatic stress disorder that turns his life upside down and reawakens old wounds. Haunted by the silence of his grandfather, a World War II veteran, he decides to travel across Europe to confront his fears, understand his past, and begin rebuilding his life. A Last Scar is the intimate portrait of a man in search of inner peace, between memory, transmission, and resilience.